Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already establish read-only/idempotent behavior, and the description adds meaningful non-obvious behavior: invalid combinations cause upstream 400 'Invalid mnemonic' errors, tri_ex_fed is defined relative to the Fed's ON RRP trades, and default measure/collateral choices are disclosed. This goes well beyond what annotations provide.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is dense but every sentence earns its place: definition, defaults, sibling differentiation, and error-handling guidance are all included without padding. Key distinctions are front-loaded and the parenthetical examples aid interpretation.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the complexity of seven optional parameters and no output schema, the description is remarkably complete. It covers the tool's scope, default behavior, expected errors, invalid-combination caveats, and alternatives, so an agent can invoke it confidently and recover from likely failures.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100%, so the schema already explains the parameters well. The description adds extra value by clarifying units (rate %, volume/outstanding $), explaining collateral segment abbreviations, and describing the tenor dimension including collateral-type splits that are not simple term buckets.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly identifies the tool as a repo market data source for rates/volumes broken out by collateral segment and tenor. It also distinguishes itself from neighboring data sources and the sibling tool ofr_search_funding_series, so an agent can tell exactly what this tool offers.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description explicitly explains when this tool is the right choice: it provides OFR's independent collateral/tenor decomposition that FRED and nyfed-markets do not offer. It also gives a fallback, directing users to ofr_search_funding_series when an invalid combination is encountered.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.